Ultra-wideband (UWB) Impulse Radio (IR) is evolving as a promising mode of wireless communication for low-power, low data rate radios. As compared to traditional Continuous Wave (CW) radios, communication in IR-UWB is based on temporally short pulses. The short-duration pulses in case of IR-UWB Radio gives one the opportunity to duty-cycle the power hungry RF circuits. This duty-cycling of the RF circuitry requires good synchronization between communicating nodes. There are various ways of synchronizing two nodes with their corresponding architectural limitations which determine the scalability of the network and the power reduction capabilities. One such implementation of interest to us is that based on Pulse-Coupled Oscillators (PCO). One such method is described in U.S. patent application Ser. No. 12/670,682, filed Feb. 22, 2010 and published with document number 2010-0190517.
This kind of system has been proposed for realizing ultra low power, globally synchronized UWB communication networks. In this kind of network, it is not necessary for all the nodes to be directly interconnected. For the network to work, nodes just need to be indirectly connected through other nodes. Thus, this system is scalable and useful for various low power, low data-rate networks such as sensor networks, human body networks etc. This scheme facilitates a global clock for the entire network, even though the nodes are not directly connected and hence can be utilized in conjunction with various types of Media Access Control (MAC) protocols.
One particular type of network application is a sensor network for the detection of particular events such as intrusion, gas leaks, fire, smoke, etc.
In view of the above discussion, it would be beneficial to have a simple method for propagating event detection through a wireless network.
It would further be beneficial to be able to approximate the distance to the event-detecting node from every other node in the network.
It would further be beneficial to have the capability of detecting different types of events and propagate differentiation information as well.